The present invention concerns a friction pad to be used in conjunction with a cartridge in any cartridge type dispenser, preferably a caulking gun type dispenser. More specifically, the invention concerns a friction pad that can be used with any existing caulking dispenser to prevent the rotation of the cartridge.
Fluid dispensers, such as caulking guns, find widespread use in industrial and household applications. They are used with standardized cartridges or xe2x80x9ctubes.xe2x80x9d The cartridges are typically provided in the form of tubes having a dispensing outlet (a conical tip or nozzle for example) disposed on one end, with the other end adapted for receiving a plunger mechanism or the like from the dispenser. Inside the cartridge""s plunger receiving end is a slidably sealed, axially-movable disc.
The cartridges may contain a wide variety of viscous substances, such as caulking material, waterproofing adhesives, lubricants and sealants, which may be useful in construction for bonding materials together, or in the home for filling in cracks of a window frame and joints of a pipe to prevent leakage.
The typical caulking dispenser is a cradle with a stop on one end and a plunger in the other. The half-tube includes a handle and trigger extending from the handle that forcibly drives the plunger along the tube. The cartridge containing caulking is inserted into the dispenser. A nozzle, integral with the cartridge, extends through a passage in the stop; the plunger inserts into the cartridge for extruding caulking through the nozzle when the plunger drives a plunger into the cartridge.
The standard cartridges and caulking dispensers that load them are successful because of their ability to dispense the material directly into a corner, groove, or crack without mess or spread of material.
It is a common practice to cut the plastic tip of the dispensing nozzle at a predetermined angle. The tip is cut in an angle because 1) it is hard to apply the fluid material if the dispenser is perpendicular to the surface; 2) the amount of material dispensed when the tip is not cut in an angle is less than an angled tip; 3) the fluid material flushes easier; and 4) it is easier to handle the dispenser in corners.
The dispensing nozzle is then moved as desired relative to the working surface, and the caulking is expelled. The angled cut provides a ready means of applying the caulking directly into the crack or onto the surface intended while the outwardly projecting top shaped by the angle smoothes the surface of the caulking. For this procedure to work properly, the angle of the cut must be moved with the direction of movement of the dispenser.
One serious drawback with the existing caulking dispensers is that it is well known that the cartridge is prone to rotate within the cradle, which holds the cartridge. This rotation causes the caulking to exit the dispensing nozzle to one side or the other of the intended point of application. When this happens, the caulking must either be removed or applied again after the dispensing nozzle has been correctly positioned or by moving the bead of caulking into its proper position by the finger. In either case, both time and materials are wasted.
U.S. Pat. No. 4,706,853 entitled xe2x80x9cCaulking Dispenser with Means to Prevent Rotation of Compound Cartridge During Use and to Provide Positive Pressure Releasexe2x80x9d to Stonesifer et al. discloses a caulking dispenser that addresses this problem. The reference avoids the rotation of the cartridge by having a caulking dispenser that includes a pair of extending prongs integrally fixed to the plunger. The prongs penetrate the contact surface disk of the cartridge.
While the Stonessifer et al. device provides satisfactory service, the manufacture of the dispenser is not optimum because it requires special complex designed parts, which will include additional cost.
Another problem presented by the Stonessifer et al. device is that most of the consumers already own a caulking dispenser, and in order to avoid the rotation of the cartridge, it will be necessary for them to buy a new dispenser.
Accordingly, the present inventor felt a need for a simplified, economical, reliable, and easy-to-use device that can prevent the rotation of the cartridge in a caulking dispenser.
There is also a need in the art for a device that is adapted to be removably mounted to a conventional caulking dispenser to prevent the rotation of the cartridge.
A prime object of the invention is to provide means for preventing rotation of a cartridge in a caulking dispenser that is of low cost, easy to use, and flexible.
It is yet another object of the present invention to provide a rotation preventing means for a caulking dispenser that is adapted to be removably mounted to a conventional existing caulking dispenser.
It is yet another object of the invention to provide means for preventing rotation of a cartridge in a caulking dispenser in order to maintain the angle of movement of an angularly cut dispensing nozzle.
It is yet another object of the invention to provide such means made up of materials that are reusable, and recyclable, and in long range may be considered degradable.
It is yet another object of the invention to provide a simple and highly efficient means for use on reciprocating plungers.
After years of working with caulking dispensers and experiencing the inconvenience of keeping the tip of the cartridge aligned with the work surface because of the rotation of the cartridge, the present inventor conceived the simple idea of adding a friction pad at the front face of the gun to prevent the rotation of the cartridge.
The present invention is a very simple way of preventing the rotation of the cartridge on existing caulking dispensers.
More particularly, the present invention contemplates in its most basic embodiment a method for preventing the rotation of a cartridge in a cartridge type dispenser, wherein the dispenser includes a cradle having a front wall on a first end and a plunger in a second end, a handle, and a trigger extending from the handle, wherein the trigger drives the plunger along the cartridge, the method comprising the steps of:
a) inserting a friction pad to the cradle; and
b) inserting the cartridge in the cradle;
wherein the friction pad is adapted to be fitted between the cradle and the cartridge, the friction pad comprising:
a front face adapted to be fitted in engagement with the cradle; and
a back face adapted to be fitted in engagement with the cartridge.
The friction pad comprises a C-shape made of layers of a single friction material.
In a first preferred embodiment of the invention, a layer of an adhesive material is bonded to the back face of the friction pad.
In a second preferred embodiment of the invention, the friction pad comprises:
a first layer having a first face and a second face, the first face of the first layer adapted to be fitted in engagement to the cradle;
a second layer having a first face and a second face, first face of the second layer adapted to be fitted in engagement to the second face of the first layer;
a third layer having a first face and a second face, the first face of the third layer adapted to be fitted in engagement to the second face of the second layer, and the second face of the third layer adapted to be fitted in engagement to the cartridge.
In a third preferred embodiment, the friction pad is shaped as a ring. The ring includes layers of a single friction material or layers of different friction materials.
In a less preferred embodiment of the present invention, the friction pad is adapted to be fitted between the plunger and the cartridge to prevent the rotation of the cartridge.
The invention contemplates using the above friction pad in conjunction with an existing caulking dispenser to prevent the rotation of the cartridge by simply placing the friction pad between the cradle and the cartridge.
The foregoing has outlined rather broadly the more pertinent and important features of the present invention in order that the detailed description of the invention that follows may be better understood, and so that the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter, which shape the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other friction pads for caulking dispensers for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent structures do not depart from the spirit and scope of the invention as set forth in the appended claims.